OGT TYPE QUESTIONS

1. OGT TYPE QUESTIONS Science

2. Stars are able to shine for billions of years. To shine, they must be able to produce massive amounts of energy. What is the main process taking place inside of a star in order for the star to produce and release energy? • A. radioactive implosion B. Nuclear Fission • C. nuclear fusion D. combustion

3. Stars are able to shine for billions of years. To shine, they must be able to produce massive amounts of energy. What is the main process taking place inside of a star in order for the star to produce and release energy? • ANSWER: B • Nuclear fusion is the process by which two or more nuclei with small masses (such as hydrogen) join together, or fuse, to form a larger, more massive nucleus (such as helium). During this process, a massive amount of energy and radioactive emissions (such as gamma rays) are produced. Combustion, and even nuclear fission, would consume too much matter, causing a star to die much too quickly.

4. Many cultures have identified groups of stars that seem to resemble objects, animals, or people. What is the term describing a section of the sky that contains recognizable star patterns? • A. a globular cluster • B. A retrograde pattern • C. A constellation • D. A nebula

5. Many cultures have identified groups of stars that seem to resemble objects, animals, or people. What is the term describing a section of the sky that contains recognizable star patterns? • Answer: C • Constellations helped astronomers in the science’s early history to organize the sky and track the apparent motions of planets and stars. Commonly recognized constellations include the Big Dipper, the Little Dipper, Ursa Major, and so forth.

6. Stars are born, go through a life cycle, and then eventually die. Where are stars formed? • A. From the planets in a solar system • B. In comets • C. In asteroids • D. In nebulae

7. Stars are born, go through a life cycle, and then eventually die. Where are stars formed? • Answer: D • A nebula is a large cloud of gas and dust spread out in an immense volume. Stars are formed from the gas and dust of a nebula.

8. A star is born when gas and dust from a nebula become so dense and hot that nuclear fusion starts. Which of the following forces is responsible for the formation of a star? • A. Gravitation • B. Friction • C. Magnetism • D. Electromagnetic energy

9. A star is born when gas and dust from a nebula become so dense and hot that nuclear fusion starts. Which of the following forces is responsible for the formation of a star? • Answer: B • The core is at the center of the sun. This is where the sun’s energy is produced through the process of nuclear fusion of hydrogen atoms.

10. Stars do not exist as separate entities in space, but instead belong to large groups of other stars that are held together by the force of gravity. What is the term describing a large grouping of stars in space? • A. A galaxy • B. A quasar • C. A pulsar • D. A nebula

11. Stars do not exist as separate entities in space, but instead belong to large groups of other stars that are held together by the force of gravity. What is the term describing a large grouping of stars in space? • Answer: A • A galaxy is a huge grouping of individual stars, star systems, star clusters, dust, and gas all bound together by gravity. There are billions of galaxies in the universe, each containing billions or even trillions of stars.

12. Our solar system belongs to the Milky Way galaxy. Which of the following terms describes the Milky Way’s classification? • A. Irregular galaxy • B. Spiral galaxy • C. Elliptical galaxy • D. Spherical galaxy

13. Our solar system belongs to the Milky Way galaxy. Which of the following terms describes the Milky Way’s classification? • Answer: B • Galaxies that appear to have a bulge in the middle and arms that spiral outward are known as spiral galaxies. Most galaxies, including the Milky Way are spiral galaxies.

14. In 1964, Arno Penzia and Robert Wilson discovered that radiation bombards Earth from all directions in space. Cosmologists reason that this radiation is cosmic background radiation left over from the big bang. What is the big bang theory? • A. A theory that states that the universe began with a tremendous explosion. • B. A theory that states that particles in the universe are constantly imploding. • C. A theory that states that the universe has no beginning and no end. • D. A theory that states that the universe is currently nothing more than a small ball of matter.

15. In 1964, Arno Penzia and Robert Wilson discovered that radiation bombards Earth from all directions in space. Cosmologists reason that this radiation is cosmic background radiation left over from the big bang. What is the big bang theory? • Answer: A • Astronomers theorize that the universe was first formed 10 to 15 billion years ago. At that time, all of the matter in the universe was melded together into an incredibly dense ball that was no more than a millimeter or so in diameter. The ball then exploded in what is known as the big bang.

16. No single rock sequence records the entire history of life on Earth. Paleontologists must compare fossils in rock sequences in one area with fossils in rock sequences in other areas in order to relate the sequences with one another. What is the term describing this process? • A. Fossil correlation • B. Radiometric analysis • C. Absolute dating • D. Rock ordering

17. No single rock sequence records the entire history of life on Earth. Paleontologists must compare fossils in rock sequences in one area with fossils in rock sequences in other areas in order to relate the sequences with one another. What is the term describing this process? • Answer: A • Fossil correlation is used to reconstruct the history of life on Earth. Although the rock types vary from outcrop to outcrop, the sedimentary rock layers contain fossils, called index fossils, that mark a specific “moment” in geologic history. Index fossils are used to correlate the fossils in one area with fossils in another area.

18. Prokaryotes were the first organisms known to have appeared on Earth. Around 1.5 billion years ago, another form of life, known as eukaryotes, evolved. Which of the following kingdoms did the first eukaryotes most likely belong? • A. Fungi • B. Archaebacteria • C. Protista • D. Eubacteria

19. Prokaryotes were the first organisms known to have appeared on Earth. Around 1.5 billion years ago, another form of life, known as eukaryotes, evolved. Which of the following kingdoms did the first eukaryotes most likely belong? • Answer: C • Today, eukaryotes are single- or multi-celled organisms, but the first eukaryotes were only single-celled. They were differentiated from prokaryotes by their nucleus. These nucleus-bearing, single-celled organisms were the ancestors of modern-day protists (as well as all other forms of eukaryotic life).

20. The oldest known fossils of multicellular organisms were found in 700-million-year-old rocks. Which of the following processes led to the evolution of multicellular organisms? • A. The development of the nucleus • B. Endosymbiosis • C. Cell differentiation • D. The evolution of organelles

21. The oldest known fossils of multicellular organisms were found in 700-million-year-old rocks. Which of the following processes led to the evolution of multicellular organisms? • Answer: C • A unicellular organism must carry out all of the activities of the organism within the structures of a single cell. Distinct types of cells in one body can have specialized functions in a multicellular organism. Therefore, the development of the ability of a cell to become differentiated led to the evolution of multicellular life forms.

22. Different radioactive isotopes have differing half-lives. The length of the half-life of a radioactive isotope determines what the isotope is most useful for dating. Which of the following types of radiometric dating is most useful for dating an object that is around 20,000 years old? • A. Potassium-argon method • B. Uranium-lead method • C. There is no radiometric dating method available for an object of that age. • D. Carbon-14 method

23. Different radioactive isotopes have differing half-lives. The length of the half-life of a radioactive isotope determines what the isotope is most useful for dating. Which of the following types of radiometric dating is most useful for dating an object that is around 20,000 years old? • Answer: D • The half-life of uranium-238 is 4.5 billion years. The half-life of potassium-40 is 1.3 billion years. The half life of carbon-14 is 5,730 years. Therefore, the carbon-14 method would be adequate to date an object that was around 20,000 years old.

24. A nonrenewable resource is a resource that can be used up faster than it can be replenished naturally. Today, people use many nonrenewable resources to make products and produce energy. Which of the following is a nonrenewable resource? • A. Wind • B. Sunlight • C. Silver • D. Trees

25. A nonrenewable resource is a resource that can be used up faster than it can be replenished naturally. Today, people use many nonrenewable resources to make products and produce energy. Which of the following is a nonrenewable resource? • Answer: C • There is only a limited amount of silver on Earth. Once all the silver has been used up, no more can be made. Resources such as trees, however, can be planted and grown to replace the ones we use, and resources such as sunlight and wind are extremely abundant and will constantly be renewed as long as our solar system’s sun burns.

26. How long does it take for new fossil fuels to be created? • A. Millions of years • B. Billions of years • C. Hundreds of years • D. Thousands of years

27. How long does it take for new fossil fuels to be created? • Answer: B • It takes millions of years for fossil fuels to form. As a matter of fact, the majority of the fossil fuels we use today were formed around 300 million years ago.

28. A renewable resource is one that is continually produced, such as the wind and sunlight. Which of the following is a renewable resource? • A. Petroleum • B. Iron ore • C. Fresh water • D. Diamonds

29. A renewable resource is one that is continually produced, such as the wind and sunlight. Which of the following is a renewable resource? • Answer: C • Some communities have a hard time providing enough fresh water for everybody, but because fresh water is constantly recycled in the environment through the water cycle, freshwater can still be considered a renewable resource. The other resources listed will someday run out if we keep using them, so we must learn to “conserve,” or limit our use.